Pacemakers deliver timed sequences of low energy electrical stimuli, called pace pulses, to the heart, such as via an intravascular lead (hereinafter referred to as a “lead”). By properly timing the delivery of pace pulses, the heart can be induced to contract in proper rhythm, greatly improving its pumping efficiency.
Defibrillators are devices capable of delivering higher energy electrical stimuli to the heart. A defibrillator is capable of delivering a high energy electrical stimulus that is sometimes referred to as a defibrillation countershock. The countershock interrupts a fibrillation, allowing the heart to reestablish a normal rhythm for efficient pumping of blood.
One problem that may arise is if a shock lead dislodges and the shock electrode shorts to either a pacing lead or another shock lead. The short may cause all of the energy from the countershock to be delivered internal to the device itself instead of to the heart which may damage the device. There is a need in the art for detection of shorted leads.